They’re in a lecture format. There are some classes that are set up as live classes that interact with Christian schools and the kids can communicate with the teacher through an IRC system. My kids just watch the lectures, do the work, and we grade their work.
The best thing is that if they register with the Academy of Home Education through BJU, and attend 9th through 12th grade, they can obtain a Highschool diploma through BJU.
Once we got to 10th grade, we used the dual credit system since we're very close to a couple state U's. But for the high school diploma, we had to jump through hoops. I actually thought we'd have to resort to the GED (since he had earned enough credits for an AA during HS, but couldn't get an AA without a high school diploma...it was like a catch-22.)
It finally turned out to be easier than they had led us to believe. We just had to sign an affadavit, get a letter from the Homeschool Office of our public school system saying we were enrolled as homeschoolers, and then present a transcript. Since most of the classes were taken at the college, the transcript was easy.
But on his college transcripts it says "HS diploma, homeschool"...on yours they'll be an actual school that awarded the HS diploma and I think that can be helpful.